Key Design Factors Research Articles

Eccentric load bearing performance of high bolt screw (HBS) active joints for prestressed internal supports in the subway excavation

This study introduces a novel High Bolt-Screw (HBS) active joint for enhancing the load-bearing performance of steel support systems used in subway foundation pits. The HBS joint addresses the limitations of traditional steel wedge joints, particularly in handling eccentric loads and tensile forces. Experimental and numerical analyses were conducted on specimens with different screw diameters to evaluate the mechanical behavior of the HBS joint under eccentric compression. Load-strain curves, load-displacement curves, and failure modes were documented to compare the performance of the HBS joint with an equal length steel support (ELSS) and a traditional wedge joint. The data and results obtained from numerical simulations exhibited a high degree of concordance with those derived from laboratory tests. Finite Element Analysis (FEA) was employed to perform parametric studies, examining the effects of key design factors such as screw diameter and eccentricity. The results indicate that the HBS joint provides superior preloaded axial force retention. Additionally, the HBS joint exhibited a yield load 1.35 times greater than that of traditional wedge joints, with an initial compressive stiffness 3.5 times higher, enhancing its resistance to deformation under eccentric loads. Parametric analysis indicated that the yield load is influenced by the eccentric distance but unaffected by the eccentric angle, with screw diameter, barrel nut height, and extension length identified as key factors. A yield load formula was derived through rigorous theoretical analysis and validated against experimental data, showing a relative error of less than 10 %. These findings emphasize the exceptional eccentric load-bearing capacity and stiffness of HBS joints, providing valuable insights for designing and implementing advanced support systems in subway foundation pit construction.

Analytical hierarchy process based stability assessment of soil nailed structures

ABSTRACT In practice the preliminary design of routine soil nailed structures is usually based on thumb rules derived from existing knowledge and local experiences. In such a scenario, judgement of project engineer is crucial in assessing the stability of the constructed structure. In the present study, the Analytical Hierarchy Process (AHP) is utilized to assess the influence of seven key design factors on the prominent failure modes of soil nailed structures. AHP is a multi-criteria decision-making process, wherein, pairwise comparisons among all influencing criteria and among different alternatives with respect to each criterion are made. The responses required to constitute pairwise comparison matrices are obtained by performing a limit equilibrium-based parametric analysis. Based on the AHP analysis, nail spacing & soil friction angle are found to be the most influencing variables to overall stability. Further, the study also proposes a parameter Composite Stability Index (CSI) for soil nailing design optimization.

Optimizing greenhouse design for enhanced microalgae production: A CFD Analysis of microclimate and water thermal dynamics in raceway ponds

The increasing demand for sustainable biomass has made microalgae farming into the spotlight as a viable source of biofuels, nutraceuticals, and other valuable products. Raceway ponds are one of the most common systems in algaculture due to their simplicity and cost-effectiveness. However, their efficiency is significantly influenced by surrounding microclimate conditions. In this study, we present a Computational Fluid Dynamics (CFD) analysis aimed at optimizing greenhouse design to enhance microalgae production in a raceway pond housed within a controlled greenhouse environment. The research focuses on evaluating the influence of greenhouse microclimate parameters on water's thermal dynamics in the pond. Simulations were conducted to assess how different greenhouse geometries and ventilation configurations affect the heat exchange between the water surface and air within the greenhouse, as well as the internal flow dynamics, both of which are critical for optimal algae growth.The results provide insights into the optimal greenhouse design parameters that maintain the optimal water temperatures in the pond while minimizing thermal fluctuations to enhance microalgae productivity. Specifically, a significant 5 °C temperature difference was observed between the pond's surface and bottom, mainly due to convective heat transfer. Key design factors, such as greenhouse height and ventilation rates, were shown to have a substantial impact on water temperature.The insights gained are essential for optimizing greenhouse design and ventilation strategies to maximize algae growth and production efficiency. This preliminary modeling lays the foundation for future sensitivity analyses aimed at refining the system, ultimately improving algae cultivation in controlled environment agricultural systems.

A Theoretical Design Framework of Contemporary Vernacular Architecture Based on a Scoping Review of the Best Practices Worldwide

This paper reviews the development of vernacular architecture design and practices worldwide and then focuses on Chinese rural development. It explores the evolution of vernacular architecture and related concepts from a longitudinal perspective, and indicates the dynamic adaptability of vernacular architecture. A scoping review based on archival materials and secondary source literature of the last 10 years is conducted. As a result, 41 design factors have been collected. With a cross-comparative study with related publications, five intangible design factors and ten key tangible design factors are discussed to build a theoretical design framework, which finally provides a foundation for related design practices and further research.

A Review on Advances and Challenges in Core-Shell Scaffolds for Bone Tissue Engineering: Design, Fabrication, and Clinical Translation.

This review explores core-shell scaffolds in bone tissue engineering, highlighting their osteoconductive and osteoinductive properties critical for bone growth and regeneration. Key design factors include material selection, porosity, mechanical strength, biodegradation kinetics, and bioactivity. Electrospun core-shell nanofibrous scaffolds demonstrate potential in delivering therapeutic agents and enhancing bone regeneration. Critical characterization techniques include structural, surface, chemical composition, mechanical, and degradation analyses. Scaling up production poses challenges, addressed by innovative electrospinning techniques. Future research focuses on regulatory and commercial considerations, while exploring advanced materials and fabrication methods to optimize scaffold performance for improved clinical outcomes.

Integrating Machine Learning and Genetic Algorithms to Optimize Building Energy and Thermal Efficiency Under Historical and Future Climate Scenarios

As the global energy demand rises and climate change creates more challenges, optimizing the performance of non-residential buildings becomes essential. Traditional simulation-based optimization methods often fall short due to computational inefficiency and their time-consuming nature, limiting their practical application. This study introduces a new optimization framework that integrates Bayesian optimization, XGBoost algorithms, and multi-objective genetic algorithms (GA) to enhance building performance metrics—total energy (TE), indoor overheating degree (IOD), and predicted percentage dissatisfied (PPD)—for historical (2020), mid-future (2050), and future (2080) scenarios. The framework employs IOD as a key performance indicator (KPI) to optimize building design and operation. While traditional indices such as the predicted mean vote (PMV) and the thermal sensation vote (TSV) are widely used, they often fail to capture individual comfort variations and the dynamic nature of thermal conditions. IOD addresses these gaps by providing a comprehensive and objective measure of thermal discomfort, quantifying both the frequency and severity of overheating events. Alongside IOD, the energy use intensity (EUI) index is used to assess energy consumption per unit area, providing critical insights into energy efficiency. The integration of IOD with EUI and PPD enhances the overall assessment of building performance, creating a more precise and holistic framework. This combination ensures that energy efficiency, thermal comfort, and occupant well-being are optimized in tandem. By addressing a significant gap in existing methodologies, the current approach combines advanced optimization techniques with modern simulation tools such as EnergyPlus, resulting in a more efficient and accurate model to optimize building performance. This framework reduces computational time and enhances practical application. Utilizing SHAP (SHapley Additive Explanations) analysis, this research identified key design factors that influence performance metrics. Specifically, the window-to-wall ratio (WWR) impacts TE by increasing energy consumption through higher heat gain and cooling demand. Outdoor temperature (Tout) has a complex effect on TE depending on seasonal conditions, while indoor temperature (Tin) has a minor impact on TE. For PPD, Tout is a major negative factor, indicating that improved natural ventilation can reduce thermal discomfort, whereas higher Tin and larger open areas exacerbate it. Regarding IOD, both WWR and Tin significantly affect internal heat gains, with larger windows and higher indoor temperatures contributing to increased heat and reduced thermal comfort. Tout also has a positive impact on IOD, with its effect varying over time. This study demonstrates that as climate conditions evolve, the effects of WWR and open areas on TE become more pronounced, highlighting the need for effective management of building envelopes and HVAC systems.

A comprehensive review of radiation shielding concrete: Properties, design, evaluation, and applications

AbstractThis review paper provides a comprehensive analysis of radiation shielding concrete, covering its properties, design, evaluation, and applications. It begins with an introduction, stating the objective and scope. The paper explores radiation shielding basics, including ionizing radiation, shielding principles, and materials used for shielding. Concrete's properties relevant to shielding, radiation attenuation mechanisms, and factors affecting its efficiency are discussed. Different types of radiation shielding concrete are examined, along with their applications. The design and formulation of shielding concrete, including mix proportions, optimization techniques, and quality control, are presented. Evaluation methods and standards are discussed. Lastly, challenges, future directions, and emerging technologies are outlined. This review paper serves as a valuable resource for professionals involved in radiation shielding. The review on radiation shielding concrete highlighted its effectiveness in attenuating ionizing radiation, emphasizing material composition, density, and thickness as key design factors. Evaluation methods, such as gamma spectroscopy and Monte Carlo simulations, are discussed, demonstrating its versatile applications in nuclear facilities, healthcare, and space exploration.

Systematic Layout Planning and Analytical Hierarchy Process for Laboratory Layout Optimization: A Case Study of DESPRIN

The Product Design and Innovation Laboratory (DESPRIN) at Del Institute of Technology plays a crucial role in supporting innovation. Yet, its current layout struggles to meet its users' diverse and evolving needs. This study addresses the problem of inadequate spatial configuration, which hampers workflow efficiency, ergonomics, and the lab's overall capacity to accommodate various activities. To resolve this issue, a flexible layout is designed using the Systematic Layout Planning (SLP) method, emphasizing optimizing space utilization, workflow, and spatial adaptability. Data collected from literature reviews, interviews, statistical analyses, and anthropometric measurements inform the design process to enhance the lab’s quality and spatial efficiency. The Analytical Hierarchy Process (AHP) is employed to prioritize key layout design factors, identifying capacity as the most critical element (0.4930), followed by facilities (0.1688), accessibility (0.1414), security (0.1270), and environment (0.0708). The study results in 13 new layout configurations that can accommodate various activities within DESPRIN, providing a more dynamic and responsive user environment.

Revealing the intricacies of natural convection: A key factor in aqueous zinc battery design

Aqueous zinc-based batteries offer high safety, abundant resources, low cost, and environmental friendliness, making them a promising alternative to lithium-ion batteries for large-scale energy storage markets. However, the natural convection in the electrolyte during operation, which can greatly affect the battery performance, is overlooked for a long time. Through particle tracing experiments, this study demonstrates that in the vertical placement of the battery, natural convection occurs due to the variation of electrolyte density, whereas it does not happen when the cathode is on top. Besides, there is a significant difference in electrochemical performance between these two configurations, with a voltage difference of up to 0.25 V at 10 mA cm⁻² and a peak current difference of up to 3.4 mA in linear sweep voltammetry. Simulation results show that convective mass transfer can be up to 100 times greater than diffusive mass transfer in a bulk solution. This highlights the importance of considering natural convection to improve model accuracy. Further, to increase energy density, batteries are scaled up in practical applications to reduce the weight of the casing. This work simulates mass transfer conditions under various scenarios, illustrating the trade-off between current density and battery size, and offering new guidance for the design of aqueous zinc-based batteries.

An overview on building-integrated photovoltaics: technological solutions, modeling, and control

The advancement of renewable and sustainable energy generation technologies has been driven by environment-related issues, energy independence, and high costs of fossil fuels. Building-integrated photovoltaic systems have been demonstrated to be a viable technology for the generation of renewable power, with the potential to assist buildings in meeting their energy demands. This work reviews the current status of novel PV technologies, including bifacial solar cells and semi-transparent solar cells. This review discusses the various constructions of PV technologies, recent advances in these products, the influence of key design factors on electrical and thermal performance, and their potential in the design of energy-efficient smart buildings. The attention is focused on bifacial and semi-transparent PV systems, given the high level of interest of the scientific community in their current and potential applications.Focus is also devoted to the analysis of the electrical, optical, and thermal modeling procedures developed for sizing, designing, and integrating photovoltaics into larger building simulations. The development of these models has a positive impact on the implementation of next-generation smart buildings. The latest innovative developments and key issues in the application of bifacial PV solutions in buildings are also summarized and analyzed. Special attention is paid to rear side electrical performance, which can be evaluated by means of illuminance/optical backside modeling. Finally, energy management and control of PV-equipped buildings via both model-based and data-driven approaches are discussed, as well as the integration of electric storage systems in a multi-building context.

Empirical Correlation of Hossaena Town Soil Index Properties with California Bearing Ratio (CBR) Values

California bearing ratio (CBR) is a key input factor in pavement structural design that is used to determine character size, the strength of unbound materials, and subgrade soils. The construction of a straightforward and logical regression model to forecast the CBR of unbound materials as a function of the index properties of the material. This work explains the relationship between compaction parameters and Atterberg limit tests. Laboratory test was conducted to get the independent (percent finer, liquid limit, plastic limit, plastic index, maximum dry density and moisture content), and dependent variables (CBR). A statistical package for social science software (SPSS) used to develop the mathematical model both in single and multiple regression. The viability of using multiple linear regression analysis to relate CBR values to soil index features was investigated. In this study, SPSS is used to examine each independent variable's significance individually. The multiple linear regression analysis was used to create the correlation, which had an eighteen-person sample size and a modest determination coefficient of R2 = 0.821. The CBR has good relation with maximum dry density and optimum moisture content compared to other parameters. This model applicable for small structure in the specified soil type, MH.

Computational Fluid Dynamics Analysis on Proton Exchange Membrane (PEM) Fuel Cell Performance using Honeycomb Flow Channel

Proton exchange membrane fuel cell (PEMFC) systems have the ability to meet our energy demands in the near future since they are green, economical, and clean. They can also use hydrogen as a direct fuel. One of the key design factors influencing the PEMFC's performance is flow field configuration. The configuration of the flow channel in a PEMFC has a profound effect on reactant distribution and water management within the fuel cell. Current study aims to ameliorate fuel cell (FC) performance, water management, and pressure drop (PD) across channels. ANSYS Fluent 18.2 software, including its PEMFC add-on module, is utilized to execute a computational fluid dynamics (CFD) simulation of a 3D model of a PEMFC with a flow channel shaped like a honeycomb structure. A polarization curve, as well as factors such as PD, hydrogen and oxygen concentrations, membrane water content, and current density distribution along flow channels, have been included in the simulation results. The findings suggest that when the FC is operated at 0.45V, homogeneous reactant consumption and greater power and current densities are achieved, and, water generation is high across the Membrane Electrode Assembly (MEA).

Carbon nanotube heat absorber for efficient direct-heating of liquid tin in a solar receiver

A new approach that use vertically-aligned carbon nanotubes (VACNT) as heat absorbers is proposed for efficient direct solar heating of liquid tin in a solar receiver integrated with beam-down optics. Plate-type CNT heat absorbers were prepared by adjusting the concentration of CNTs in the processing solvent m-cresol. The prepared CNT absorber exhibited an increase in bulk density and the formation of a densely packed nanotubes skeleton with a higher CNT concentration in m-cresol. Thermal conductivity, a key design factor for solar absorbers, showed a stronger correlation with skeletal density than with bulk density. Heat absorption characteristics of the solar liquid tin receiver (50 mm-i.d., 60 mm-high) with the CNT absorbers integrated with a Fresnel lens (0.98 m i.d.) were determined. The tin temperature in the receiver with the CNT absorber reached a maximum of 728 °C. Bare tin exhibited system efficiency of 27.7 % and receiver efficiency of 38.3 %, but tin heating through the CNT plates exhibited system efficiency of up to 48.4 % and receiver efficiency of 64.3 %, showing a system heat absorption rate 1.75 times higher. The thermal absorption efficiency was proportional to the skeletal density of the plates, and the thermal absorption of the system was dominated by the efficient transfer of absorbed heat in the energy absorption region. The energy flow and heat loss in the receiver system were analyzed. Although the bare tin receiver exhibited a high heat loss of 27.1 % owing to the low emissivity or high reflectivity of the tin surface, the heat loss in the CNT absorber plates with high absorptivity was only 0.9 %. The flat plate-shaped transmission window in the receiver caused significant reflective heat loss and convective heat loss owing to head-on wind. Based on the energy flow analysis, improvement approaches for enhancing the thermal efficiency of the proposed receiver system are suggested.

Two-Regime Conformation of Grafted Polymer on Nanoparticle Determines Symmetry of Nanoparticle Self-Assembly.

One of the key design factors that regulate the properties of grafted nanoparticles (GNPs) and their self-assembly is the conformation of the grafted polymer. On the curved surface of the GNP core, the conformation of the polymer chain is not uniform in the radial direction. The segment is a non-Gaussian chain in the concentrated polymer brush (CPB) regime near the interface between GNP core and grafted polymer, while it is less constrained in the semidilute polymer brush (SDPB) regime near the surface of GNP. Here, the property of polymer conformation showing crossover behavior at the CPB/SDPB threshold through the coarse-grain molecular dynamics simulation of nanoparticles with explicit grafted chains is explored. Moreover, the self-assembly structure depends on the effective softness, which is defined as a function of the threshold of two regimes estimated from the conformation of the polymer.

Strategies for Enhancing Audience Engagement in Cultural Exhibition Space Design

In this study, we explored strategies to enhance audience engagement through cultural exhibition space design. Utilizing the Evaluation Grid Method (EGM) and the Kano Two-Dimensional Quality Model, this research aims to identify key spatial design factors that influence emotional and cognitive engagement from the consumer's perspective. This includes examining how spatial layout, interactive devices, and the presentation of cultural elements can enhance the overall experience of the audience. The research methodology combined in-depth interviews and surveys, providing data that helped us analyze which design features most effectively capture and maintain audience interest and participation. The findings of this study offer specific guidance for cultural exhibition designers to improve exhibition space design, thereby attracting more audience participation and enhancing the educational and entertainment value of exhibitions. The study emphasizes the importance of innovative space design in increasing audience engagement in cultural exhibitions, providing an empirical foundation for future exhibition design practices.

Multi-objective design optimization and physics-based sensitivity analysis of field emission electric propulsion for CubeSat platforms

Field-emission electric propulsion is an electrostatic space electric propulsion technology that offers various advantageous features including efficient design, high specific impulse, and versatile thrust capabilities ranging from micro-Newton to milli-Newton levels. These characteristics make this type of propulsion a promising technology for small satellite platforms, enabling precise attitude control, orbit maintenance, and de-orbiting through ionization and acceleration of a liquid metal propellant. The growing demand for small propulsion systems in CubeSat platforms has spurred significant progress in modeling and characterizing field emission electric propulsion thrusters to enhance their overall performance. However, little study has been conducted to investigate the effect of geometric configurations on electric fields or expelled ion trajectories for design optimization. In this study, multi-objective design optimization is performed by incorporating electrostatic simulation coupled with an analytical performance model into evolutionary algorithms based on prediction from surrogate modeling, aiming to optimize the thruster emission design to maximize thruster performance. Physical insights into the key design factors influencing the performance of field emission electric propulsion have been gained by probing into the interaction between ion particles and electric field behavior within the thruster. It has been found that the length of the emitter tip has a significant effect on plume divergence, i.e., a longer emitter tip under the influence of electric field at higher emitter current tends to result in lower initial acceleration of emitted ions and subsequently wider spread or divergence of the ion beam. A shorter emitter tip, on the other hand, generates a sharper E-field gradient, resulting in a more focused and narrower ion beam. Additionally, sensitivity analysis has identified the mass flow rate and potential distributions as the most influential design factors on performance due to the active roles they play in the performance generation process.

Heart of the future home: a multidimensional model of inclusive kitchen for older people in the UK

With the development of smart technology and aging societies, the living and housing environments for older people are undergoing transformation. Designers must understand the changing capabilities, lifestyles, preferences, and inspirations of older people for their future homes, in which the kitchen is seen as the heart. To gain a deeper understanding of the requirements of older people in promoting healthier lifestyles and inclusive daily practices, the authors identified five key factors of kitchen design through a literature review, developing an initial model. Subsequently, a focus group was conducted in the UK to explore the perspectives and expectations of older people, where metaphors for future kitchens were collected, and further insights were used to refine the model. The refined model for a future-inclusive kitchen encompasses six dimensions: Environment/space, Technology/interaction, Emotion/affect, Health and safety, Human factors and well-being, and Sustainability. Through using metaphors, this study offers a multidimensional lens to investigate the future user experience of inclusive kitchens. The significance of this study lies in the originality of combining a literature review, and user study with design metaphors. A future-proof inclusive kitchen design model is proposed to provide guidance for future design directions of age-friendly environments.

Analyzing the Satisfaction of Coworking Space Users in Terms of Control

Due to technological developments that have changed the way people work, office interiors are also evolving and there has been an accelerating transition from conventional offices to shared workplaces since the rise of flexible working. These coworking spaces are intended to offset the negative effects of home-office and remote working, such as isolation and lack of collaboration. However, coworking places are more likely to improve performance and well-being when their users are given control. Accordingly, drawing on the concept of control developed by Evans and McCoy (1998), this study analyzed the satisfaction of coworking space users in terms of key control-related design factors, namely flexibility, indoor environmental control including thermal quality, air quality, visual quality, acoustic quality and furniture and layout, privacy, and territoriality. Data were collected via a survey conducted of the users of Originn Coworking Offices, İzmir, and via interviews with its founders. The findings indicate that users feel more satisfied resulted with an increased job satisfaction and productivity if they have control over their space. These findings can guide professionals in designing and constructing shared offices to meet the expectations of users, and in designing and developing existing coworking spaces.

Designing preschool children's educational games for enlightenment through decision analysis methods

As an innovative form of digital online education, educational games have potentially significant impacts on preschool children's enlightenment education. Identifying key factors for effective design is crucial in game development. This study identifies key factors for the design of educational games aimed at preschool children's enlightenment through decision analysis methods. The specific research steps include using SET analysis method to identify gaps in development opportunities, employing the Analytic Hierarchy Process to construct an interactive system design model for enlightenment educational games, calculating the weight value of each factor, and pinpointing the key factors for design practice. Based on this methodology, an enlightenment educational game has been developed, and Fuzzy Comprehensive Evaluation method has been utilized to assess the practical implementation. The approach outlined in this study enables designers to swiftly recognize the critical elements in designing educational games for preschool children's enlightenment, facilitating a responsive design process, achieving effective game designs, and ultimately enhancing preschool children's learning interest and outcomes.

Optimizing a dew point evaporative cooler in data center applications

Abstract The escalating energy consumption of data centers has led to a pressing need for energy-efficient cooling solutions. This paper presents a countercurrent dew point evaporative cooler (DPEC) for data center refrigeration. We developed and experimentally validated a numerical model for DPEC, then formulated regression models using the response surface method. These models link eight key design factors, including geometrical and operational factors, to three performance indices: cooling capacity per unit volume, coefficient of performance, and outlet primary air temperature. We assessed the extent of factor influence on these indices. By using these regression models as objective functions, we used the genetic algorithm for design optimization under two climatic conditions, resulting in various optimal parameter combinations. Our findings highlight the strong predictive accuracy of these models. In comparison to the original design, the optimal design achieved an improvement of 104.8%, an increase of 23.9%, and a reduction of 13.8% in the three indices.